arXiv 0809.05052008-09cond-mat.othercond-mat.supr-con

Metastable superfluidity of repulsive fermionic atoms in optical lattices

Achim Rosch, David Rasch, Benedikt Binz, Matthias Vojta

备注：: 4 pages, 3 figs; (v2) final version as published
发表信息：: Phys. Rev. Lett. 101, 265301 (2008)
DOI：: 10.1103/PhysRevLett.101.265301

英文摘要：

In the fermionic Hubbard model, doubly occupied states have an exponentially large lifetime for strong repulsive interactions U. We show that this property can be used to prepare a metastable s-wave superfluid state for fermionic atoms in optical lattices described by a large-U Hubbard model. When an initial band-insulating state is expanded, the doubly occupied sites Bose condense. A mapping to the ferromagnetic Heisenberg model in an external field allows for a reliable solution of the problem. Nearest-neighbor repulsion and pair hopping are important in stabilizing superfluidity.

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